1-hydroxy-4-(6&#39;-benzodioxan-1&#39;, 3&#39;) amino anthraquinone



Patented Mar. 20, 1951 UNITED STATES 2,546,121 PATENT OFFICE l-HYDROXY- l- 6'-BENZODIOXAN-1',3') AMINO ANTHRAQUINONE Saul R. Buc, Easton, Pa., and Edgar E. Renfrew, Phillipsburg, N. J assignors to General Aniline & Film Corporation,

ration of Delaware New York, N. Y., a corpo- No Drawing. Application December 10, 1949,

Serial No. 132,393

O NH; II I This dyestuff which yields a blue shade has the disadvantage that it is susceptible to gas fading.

It has now been discovered that an anthraquinone dye of the formula:

II I

0 CHa NH 5 [l-hydroxy 4 -(6-benzodi0xan-1',3') amino anthraquinonel may be prepared which gives a bluish-violet shade 0n acetate rayon and that this dye is particularly resistant to gas fading. It is also fast to light and washing.

The following example illustrates a preferred method for preparing the dyestuif but variations and substitutions may be made within the scope of the claims.

Example In a suitable vessel was placed 18.0 parts by weight quinizarin, 6.0 parts leucoquinizarin, 16.6 parts G-amino-1,3-ben odi0 in, 12.0 parts boric acid and 180.0 parts absolute alcohol. The mixture was stirred at the reflux temperature for sixteen hours, after which it was allowed to cool. The solid which separated was removed by filtration and washed thrice with denatured alcohol. The cake was suspended in 500 parts water and at 80 C. was added 3.5 parts sodium perborate. The mixture was stirred briefly and illtered, the cake was well washed with water. The cake wasthen added to a stirred solution of 500 parts water containing 25 parts sodium hydroxide solution (20% by weight). The suspension was heated for one-half hour at 80 C. and filtered. The aqueous base leach was repeated twice more and the cake from the final filtration washed alkali-free with water. The product 2 when dried and dispersed with a suitable agent dyed cellulose acetate fibers in attractiv blueviclet shades of excellent properties, especially that of fastness to acid-gas fumes such as found 5 in combustion gases.

The fastness to gas fading was about 3 units based upon procedure described in the 1949 Technical Manual of'the American Association of Textile Chemists and Colorists, pages 96 and 10 97. The reaction may be represented as follows:

0 fl E I OH: 0 H

0 (T CH. NH M014:

We claim: 1. A new dyestuff of the formula:

II I 2. A process for preparing a dyestufi of the formula:

0 OH 40 H I o w 1 I ti NH- 4) REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date v 2,254,230 Lubs et'al Sept. 2, 1941 Dickey Dec. 18, 1945 

1. A NEW DYESTUFF OF THE FORMULA: 